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11.
K J Atabekov L G Tyulkina O V Karpova V G Metelev N P Rodionova Z A Shabarova J G Atabekov 《FEBS letters》1988,232(1):96-98
The TMV RNA molecule can be cleaved at a single site by RNase H directed by chimeric oligo(deoxyribo-ribo)nucleotide with an internucleotide pyrophosphate bond. 相似文献
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SA Carrasco 《New Zealand journal of zoology.》2013,40(1):32-45
This study combined morphological and morphometric information on egg clutches, egg capsules and paralarvae of two sympatric coastal octopuses from New Zealand waters, Octopus huttoni and Pinnoctopus cordiformis, to provide species-specific traits to identify their early life stages obtained from field surveys. Eggs of O. huttoni (2.5 mm length; 1 mm width) were entwined with one another forming strings that ranged from 11 to 25.8 mm in length. Eggs of P. cordiformis (6.4 mm length; 1.5 mm width) were significantly bigger than those of O. huttoni and were grouped in small clusters of about seven eggs. Paralarvae O. huttoni and P. cordiformis differed in hatching size (1.4 mm versus 3.1 mm mantle length), number of suckers per arm (four versus eight), number of lamellae per outer demibranch (five versus ten) and arrangements of chromatophores in the body surface (29 to 59 versus 91 to 179), respectively. The morphological traits described in hatchlings from the laboratory allowed comparisons with field-collected paralarvae, suggesting that such characters were reliable species-specific patterns to enable a consistent differentiation between the early life stages of these two sympatric species, even in the absence of the brooding female. 相似文献
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Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium. 相似文献
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Detection of Treponema pallidum DNA and RNA in clinical material from patients with syphilis at different stages 总被引:2,自引:0,他引:2
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A novel peptide recognition mode revealed by the X-ray structure of a core U2AF35/U2AF65 heterodimer
U2 auxiliary factor (U2AF) is an essential splicing factor that recognizes the 3' splice site and recruits the U2 snRNP to the branch point. The X-ray structure of the human core U2AF heterodimer, consisting of the U2AF35 central domain and a proline-rich region of U2AF65, has been determined at 2.2 A resolution. The structure reveals a novel protein-protein recognition strategy, in which an atypical RNA recognition motif (RRM) of U2AF35 and the U2AF65 polyproline segment interact via reciprocal "tongue-in-groove" tryptophan residues. Complementary biochemical experiments demonstrate that the core U2AF heterodimer binds RNA, and that the interacting tryptophan side chains are essential for U2AF dimerization. Atypical RRMs in other splicing factors may serve as protein-protein interaction motifs elsewhere during spliceosome assembly. 相似文献
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N. N. Rodionova E. Z. Bibineyshvili A. R. Brazhe A. I. Yusipovich G. V. Maksimov A. B. Rubin 《Biophysics》2014,59(1):83-85
Using Raman spectrometry and fluorescence microscopy, we studied the rearrangement of carotenoid molecules and membrane-bound Ca mb 2+ in myelinated nerve fibers after K+ depolarization, K+-channel blocking, and altering the membrane protein conformation. We observed a decrease in Ca mb 2+ and an increase of microviscosity in myelin after depolarization. Changes in Ca mb 2+ and microviscosity were registered after blocking the K+ channels and modifying proteins with PCMB. Our results suggest an interconnection between the condition of nerve fiber membrane proteins, Ca mb 2+ distribution, and myelin microviscosity. 相似文献